Hi all,
If at first you don't succeed! After alot of farting about I redesigned things and thanks to John in TX's suggestion now have a perisistalic pump driven by a stepper motor and a heat exchanger to warm the milk as it flows! Its far from finished but is feeding calves now! Here it is http://www.youtube.com/watch?v=ubSJsccsfN8
I wanted to post this at the end of my initial thread but its now to old! I'm very slow!!!
Thanks to everyone who has helped, Geoff

Its still work in progress! My plan is to make it adjust according to age, at the moment they all get 1 litre four times a day, I've just got to keep bashing away at the programme, but the basic concept works.

Hi all,
If at first you don't succeed! After alot of farting about I redesigned things and thanks to John in TX's suggestion now have a perisistalic pump driven by a stepper motor and a heat exchanger to warm the milk as it flows!

Click to expand...

Wow!

What triggers the milk flow? The calf by sucking / pushing something?

If for any reason the calf has the nipple in his mouse but is not sucking, will the milk flow anyway?

The pump only goes when the calf sucks, this is sensed by a pressure sensor in the pipe feeding the teat, if they dont suck they dont get milk! The calves have rfid eartags so if they've had their allowance of milk the pump wont go.

The teats are pretty standard for feeding calves.

I have to stand there holding a bucket with a teat on it, this replaces me and does a better job, we don't have that many calves but somtimes its about 40 to be fed, this also gives them four small feeds rarther than two larger ones, better for the calf. Also I've better things to do!!

I've been looking for a way to check that there is still milk avalible to be pumped, I think a ir sensor would be the way to go but have never done anything with ir before.

I've looked about the net a bit and most of the beam break circuits use some kind of modulation on the ir emitter then some filtering on the reciver, I guess this is to stop any stray ir affecting the sensor?
I have found a couple of examples that just have the emitter 'on' and the reciver as a switch.

I have clear pipe and milk is quite opaque, I'm going to have to make a holder for the emitter and reciver, this would stop any stray ir getting in, do folks think its worth going to the trouble of modulation? I do have a pwm free on the pic! Always end up with a question.
Thanks Geoff